Coffer-dam.



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COFFER DAM.

APPLICATION FILED JULY H. 1917.

1 ,277, 847 Patented Sept. 3, 1918.7

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ELIAS CAHN, OF NEW YORK, LN. Y.

COFFEE-DAM.

Specification of Letters Patent. Patented Sept. 3, 1918.

Application filed July 11, 1917. Serial No. 179,855.

To all whom it mag concern:

Be it known that I, ELIAS CAI-IN, a citizen of the United States, residing at Bronx, in the county of Bronx, city and State of New York, have invented certain new and useful Improvements in Coffer-Dams, of which the following is a specification.

My invention relates to colferdams of the type constructed of interlocking steel sheet piles.

The purpose of my invention is to produce a cofferdam having a maximum degree of water-tightness and stability which will take up a minimum space and be suitable for use with large heads of water.

In cofferdams heretofore known and emloying steel sheet piling, only a single line of filled steel sheet pockets has been used,

which acted either merely as a core wall,

with embankments on both sides thereof to furnish stability, or with an embankment of earth on the outer or water side to assist in preventing leakage, the material in the pockets furnishing stability. If any water tended to leak through the pockets, it carried along the earth of the outer embankment and thus tended to fill up any crevices.

These coflerdams because of the embankments took up much valuable space and also the sheet pile pockets always retained a certain amount of water in them depending on varying conditions. This water in the case where no embankment is placed along the inner side of the line of pockets increased the pressure tending to burst the piles apart,

thus requiring numerous cross sheet pile partitions or ties. It also lowered the stabilizing eifect of the filling. The lowering of the level of water in the pockets could only be secured at the expense of the water-tightness of the structure.

The object of my invention is to construct a cofferdam of interlocking sheet piles or the like without the use of embankments, which shall be very water-tight and stable. This is essentially accomplishedby the use of a double row of pockets or compartments,

which shall perform the functions of rendering the structure water-tight and stable, more economical of space and forv equal efliciency more economical of material than those now in use. 7

Other objects of my invention will appear in the following description and drawings which illustrate a preferred embodiment of my invention, and in which 1 Flgure 1 represents a plan view of a portion of my new andimproved cofi'erdam,

Flg. 2 1s a section thereof, Figs. 3 and 4 are detail views showing the connections between the respective sheet piles.

. The cofierdam is constructed essentially of interlocking sheet piles 1 of any suitable shape, such as the one shown in the drawings which are connected by continuous transverse piles or partitions 2 which act as ties to resist the bursting pressure of the.

filling. The sheet piles 1 have their'parts interlocked by any suitable -mean's such as the ball and socket arrangement shown at d, the sockets tightly gripping the balls so that they cannot be separated under ordinary tinuous transverse piles 2 by angle irons having the ball and socket arrangement before mentioned and shown at 5. The outer compartments 6, that is thosefladjacent the water, are made as narrow as possibleand are filled with a fine material such as clay, which will render these compartments 6 very water-tight but which adds but little to the stability of the. structure. In a cofi'erdam fifty feet deep I prefer to make these chambers 6 about ten feet deep. The depth of the cofi'erdam is substantially the height of the water pressure. The compartments 7 i are filled with coarse, heavy material such as sand, gravel or stone which are not watertight but lend great stability to the structure. The clay filling in compartment 6 is preferably carried a little higher than the stone or other coarse filling inthe compartment 7 in filling the structure which gives just enough tension in the jaws of the interlocks of the piles 3 to tighten them and increase the impermeability of compartment 6. Thus, although the final level of the fillings in compartments 6 and 7 may be the same, the piles 3 will be tightened because the material in (3 has been kept a little higher than in 7 during the fi1ling,.and because the finer filling and water in (3 has a greater pressure.

The inner row of piles need not be driven-co1 down to the rock but may be driven into the gravel above the rock like the outer row so as to make a substantlally water-tight connection and wlthln a SUl'llClGIlt distance-of the rock bottom to destroy its effectivenessas a water barrier so that there is no possibility for any water being retained in the compartments 7. p

This structure, although it requires an extra row of piles 3, diminishes the need for transverse partitions 2 so that the entire structure requires less steel than the known structures before mentioned.

The completed structure has the filling in compartments 6 completely saturated with water, while the compartments 7 will be and I will remain completely drained of wat er.

I have described a preferred embodiment of my invention but it is clear that numerous changes and omissions can be made in the details thereof without departing from its spirit as defined in the following claims l. A cofferdam having in combination a continuous double series of adjacent but separate compartments forming a continuous wall, said compartments being con structed of interlocked sheet piles having vertical, permeable joints, and including threesubstantially parallel rows of the said piles, the innermost and outermost of said rows being connected by transverse piles,

to which the intermediate row is interlocked,

the outer compartments being filled with a water-tight material, and making a substantially water-tight connection with V the foundation, and the inner compartments being filled with a coarse, heavy material and bein so aermeable that the are alwa s substantially free from water, the said compartments and their filling furnishing all the stability for the said dam.

2. A cofferdam having in combination a continuous double series of adjacent but separate compartments forming a co1itinuous wall, said compartments being constructed of interlocked sheet piles having vertical, permeable joints, and including three substantially parallel rows of the said piles, the innermost and outermost of said rows being connected by single transverse piles, to which the intermediate row is interbein filled locked, the outer compartments with a water tlght material, and ma lzing a' 111g above said rock substantially water-tight connection with the foundation, and the inner compartments being filled with a coarse, heavy material which is permeable to water, so that they always remain substantially free from water.

3. A cofferdam resting on a. rock foundation and having in combination a continuous double series of adjacent but separate compartments forming a continuous wall, said )artments being constructed of interlocked sheet. piles having vertical, permeable joints, and including three substantially parallel rows of the said piles, the innermost and outermost of said rows being connected by transverse piles, to which the intermediate rowis interlocked, the outer compartments being filled with a watertight material, and making a substantially water-tight connection with the foundation, and the inner compartments being substantially free from water and being filled with a coarse, heavy material which is permeable to water, the bottoms of innermost walls befoundation.

l. A cofferdam composed of outer and inner walls of interlocked sheet piles having vertical, permeable joints, transverse piles connecting said walls, a third row of piles substantially parallel to the outer mentioned rows and interlocked to the said transverse piles, and separating the space between the said rows of piles into a double series of compartments, the outer compartments being filled with water-tight material and making a substantially water-tight connection with the foundation, and the inner coinpartments being free to the passage to water and filled with a coarse, heavy material permeable to Water, the interlocks of the said third row of piles being under tension.

5. A cofferdam composed of interlocked sheet piles having vertical, permeable joints and comprising a double series of adjacent and interlocked but separate compartments forming a continuous wall, the outer com partments being filled with a watertight material and making a substantially watertight connection with the foundation, and the inner compartments being substantially free to the passage of water and filled with a coarse, heavy material which is permeable to water, the said outer compartments being of a minimum depth for substantially preventing the passage of water.

6. A cofierdam composed of interlocked sheet piles having vertical, permeable joints and comprising a double series of adjacentand interlocked but separate compartments forming a continuous wall, the outer compartments being filled with a water-tight material and making a substantially watertight connection with the foundation, and the inner compartmentsbeing substantially free to the passage of water and filled with a coarse, heavy material which is permeable to water, the said outer compartments being substantially one-fourth of the depth of the said inner compartments.

7. A coflerclam constructedof interlocked sheet piles having vertical, permeable joints and comprising a continuous double series of adjacent and interlocked but separate go compartments forming a continuous wall,

water so that they are always substantially 15 free therefrom.

In testimony whereof I hereunto aflix my signature.

ELIAS CAI-IN.

copies of this patent may be obtained for five cents each, by addressing the Commissioner of Patents, Washington, D. 0. 

